Hye，
我有表AddClient，它有这样的数据
idClient NameClient Balance Date
CL-MK Muhammad Kashif CL-MK 9000 2016-10-01
CL-MA Asim CL-MA 8000 2016-10-01
CL-MQ Qasim CL-MQ 7000 2016-10-01
CL-MS Saim CL-MS 1000 2016-10-01
CL-MF Fahad CL-MF 3000 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MA Asim CL-MA 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MK Muhammad Kashif CL-MK 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
CL-MS Saim CL-MS 2016-10-01
CL-MK Muhammad Kashif CL-MK 409005 2016-10-01
CL-MK Muhammad Kashif CL-MK 400000 2016-10-01
CL-MA Asim CL-MA 566340 2016-10-01
CL-MA Asim CL-MA 560000 2016-10-01
CL-MS Saim CL-MS 401005 2016-10-01
CL-MS Saim CL-MS 400000 2016-10-01
CL-MF Fahad CL-MF 2016-10-01
CL-MQ Qasim CL-MQ 2016-10-01
在Balance列中，空格等于null
我正在尝试此查询以获得每个客户端的最低余额
SELECT idClient,NameClient,min(Balance) from AddClient group by NameClient
但结果显示像这样
CL-MA Asim CL-MA 560000
CL-MF Fahad CL-MF 3000
CL-MK Muhammad Kashif CL-MK 400000
CL-MQ Qasim CL-MQ 7000
CL-MS Saim CL-MS 1000
在客户名称Asim和Kashif中没有显示正确的结果
Asim的最小余额为8000，Kashif为9000
哪里出错？
答案 0 :(得分：0)
您需要按客户端的ID和名称对这两者进行分组，而不是仅按名称进行分组：
SELECT idClient, NameClient, min(Balance)
FROM AddClient
GROUP BY idClient, NameClient
此外，您用于平衡的数据类型似乎不是数字类型 - 这可以解释您看到的奇怪结果。如果数据类型不是数字，则应首先将其转换为数字类型。下面的代码假设Balance列中的所有值都可以转换为整数值，否则您将获得异常：
SELECT idClient, NameClient, min(CAST(Balance as INTEGER))
FROM AddClient
GROUP BY idClient, NameClient